ci(github-pages): Solve cascade of workflows

Author: espzav

.github/workflows/build-examples-launchpad.yml

@@ -4,6 +4,8 @@ on:
   push:
       branches:
       - master
+  pull_request:
+    types: [opened, reopened, synchronize, labeled]
 
 jobs:
 

.github/workflows/deploy_gh_pages.yml

@@ -3,7 +3,6 @@ name: Deploy GitHub Pages
 on:
   workflow_run:
     workflows:
-      - Build examples for Launchpad
       - Release Checker
     types:
       - completed

.github/workflows/release_checker.yml

@@ -1,11 +1,11 @@
 name: Release Checker
 
 on:
-  push:
-      branches:
-      - master
-  workflow_dispatch:  # can be run manually
-
+  workflow_run:
+    workflows:
+      - Build examples for Launchpad
+    types:
+      - completed
 
 jobs:
   build-and-deploy: